Interesting. I use 23.6gn Varget with 77gn Sierra MK's. 25.5gn with 69gn SMK's. The Axis only has a 24in barrel. I've used Hornady 75gn ELDM but for some reason they seem to drift more in wind than the MK's. Haven't figured that part out as they should perform almost the same. I use Remington BR primers.

I have also found that the groups are not affected much by several tenths of a grain of powder. And I use mixed brass, including military, just whatever I pick up off the range. If I were chasing that last 1/4MOA I would probably have to pay more attention to those details. But, consistent less than MOA groups with some 5round bug holes are good enough for me. I know from looking through the scope that I cannot hold less than 1/2 MOA consistently.